Turbo superchargers, operated by the exhaust gases from an ICE, are well known. When applied to Diesel engines, and particularly to large Diesels, the energy in the exhaust gases may be in excess of that required to provide compressed supercharged air to the engine. German Pat. No. 962 764 is directed to a supercharged ICE in which excess energy is derived from the exhaust gases by coupling the exhaust gases to a separate auxiliary turbine, serially with the supercharging turbine, if the exhaust gases contain such excess energy. The coupling includes a gear drive train with a controlled clutch, which can be coupled to the engine drive shaft and thus provide additionally energy to the motor drive shaft, derived from the excess energy in the exhaust gases. It has been found that, particularly in large engines, the losses in this energy recuperation are high; the lines to the auxiliary engine are comparatively long and, if the auxiliary engine is located in the immediate vicinity of the supercharging engine, the drive train to the engine drive shaft requires a substantial number of rotary engine transmission elements which, again, renders the system complex. Particularly, however, the auxiliary turbine must be matched in its power output and speed to the exhaust gas turbine of the supercharger and, additionally, to the output of the primary or principal engine. It is, thus, necessary that, particularly in large engines, the energy recuperation involves undesirable compromise designs. The comprise must be made because the spatial relationship in a large-size ICE, typically a Diesel ICE, does not permit optimal contact arrangements of the auxiliary turbine and the supercharging turbine with respect to the main engine drive shaft. It is, therefore, extremely difficult to recuperate excess energy derived from the exhaust gases, and such energy recuperation as can be effected is converted into rotary energy only at very low efficiency.